1. Field of the Invention
This invention relates to the loading and unloading of gondola railroad cars and more particularly, to an access and support apparatus for loading and unloading gondola railroad cars in a quick and efficient manner using a crane-type crawler. In a preferred embodiment the access and support apparatus of this invention is characterized by a trailer-mounted ramp adapted for manuevering in close proximity to the gondola railroad cars, and multiple, fixed or adjustable pallets adapted for spanning the top width of the gondola railroad cars and supporting the crane-type crawler. In a typical application, a flat bed trailer is backed to position the trailer-mounted ramp at the end of an open-top gondola railroad car above the coupler and the crane-type crawler is used to lift several pallets on top of the gondola railroad car. The crane-type crawler then ascends the ramp from the trailer to the pallets located on the gondola railroad car to facilitate unloading the gondola railroad car by an electromagnet, bucket, grapples or other material-handling device. The crane-type crawler traverses the top of the gondola railroad car by repositioning the pallets from the rear to the front of the crawler in sequence, to allow complete loading or unloading of the gondola railroad car. The pallets can also be placed over the space between coupled gondola railroad cars to facilitate continual traversal of a string of gondola railroad cars by the crane-type crawler without requiring dismounting of the crawler from the top of the cars.
One of the problems which exists in the loading and unloading of railroad cars and open-top gondola railroad cars in particular, is the lack of facility for accessing the interior of the cars with lifting devices such as cranes and other loading and unloading apparatus. Cargo such as scrap metal and the like may be loaded and unloaded from gondola railroad cars using electromagnets mounted on the arms of cranes, but the cranes must be properly positioned to access the interior of the gondola railroad cars without damaging the cars or the cranes.
2 . Description of the Prior Art
Loading of railroad cars such as open-top gondola railroad cars has been achieved in the past by using cranes mounted on railroad flat cars, as described in the Pierce Pacific Catalog included in the Information Disclosure Statement filed with this application. Other techniques include loading cross-ties in one end of the gondola car and operating a crane-type crawler inside the gondola car on the cross-ties to effect the loading or unloading operation. U.S. Pat. No. 4,175,902, dated Nov. 27, 1979, to Herzog, et al, details an "Apparatus for Loading and Unloading Railroad Cars". The apparatus includes a mobile wheeled device for loading and unloading an opentop gondola railroad car using power-actuated front and rear boom structures. A front supported foot is engageable with the upper surfaces of the railroad car sidewalls and is connected to the free ends of a front boom structure and similarly engageable rear supported feet are connected to the ends of outrigger arms movable outwardly from the sides of the rear end of the mobile apparatus. The rear boom structure includes an articulated material-engaging grapple for effecting the loading and unloading operations. U.S. Pat. No. 4,190,394, dated Feb. 26, 1980, also to Herzog, et al, details a "Method for Unloading and Loading Railroad Cars", which method utilizes the apparatus detailed in U.S. Pat. No. 4,175,902. Another "Method and Apparatus for Loading and Unloading Railroad Gondola Cars" is detailed in U.S. Pat. No. 4,723,886, dated Feb. 9, 1988, to Larry E. Frederking. The method and apparatus are designed for loading and unloading gondola railroad cars having spaced, parallel side walls with upper supporting surfaces. The apparatus includes a hydraulic excavator having a boom structure and material-engaging device mounted on two tracks, the two tracks being adjustable inwardly and outwardly from the base of the hydraulic excavator to vary the distance between the tracks. Each of the tracks has a lip connected thereto, which extends downwardly adjacent to the upper surface of the parallel side walls of the gondola railroad car to prevent the hydraulic excavator from falling from the car when the two tracks are resting on the side walls of the car. An "Apparatus For Loading and Unloading Railroad Gondola Cars" is detailed in U.S. Pat. No. 4,830,562, dated May 16, 1989, also to Larry E. Frederking. The patent details a hydraulic excavator provided with a boom structure and a material-engaging device rotatably mounted on two tracks for moving a hydraulic excavator from one location to another. Each of the two tracks has an inside set of rollers and an outside set of rollers for supporting the track over its entire width and an adjusting structure for moving the tracks inwardly and outwardly to vary the distance between the tracks. A track support apparatus is also included for supporting the track connected to the adjusting structure and multiple arms are connected to the outside of each of the track support apparatus to prevent the hydraulic excavator from falling from the gondola car when the two tracks are resting on the upper surfaces of the car.
It is an object of this invention to provide new and improved apparatus for loading and unloading railroad cars and particularly, gondola-type railroad cars using a crane-type crawler, which apparatus includes a trailer-mounted ramp for positioning in close proximity to the gondola railroad car and at least two specially designed pallets located on top of the gondola railroad car to receive and support the crane-type crawler.
Another object of this invention is to provide an access and support apparatus for loading and unloading gondola railroad cars using a crane-type crawler, which apparatus includes a trailer-mounted ramp adapted for positioning adjacent to the end of a gondola railroad car above the coupler and at least two fixed or adjustable pallets adapted for spanning the top of the sides of the gondola railroad car and supporting the crane-type crawler as the crawler is unloaded from the trailer onto the ramp and then on the pallets, wherein the gondola railroad car is loaded or unloaded by the crawler as the crawler successively traverses the pallets, moving each pallet in sequence from the rear to the front of the crane-type crawler.
Still another object of this invention is to provide new and improved fixed pallets for removably positioning on the top of a gondola railroad car and supporting a crane-type crawler and loading or unloading the gondola railroad car.
Still another object of the invention is to provide new and improved adjustable pallets for spanning the top width of a gondola railroad car in adjustable relationship to compensate for the bulging center section of the car and supporting a crane-type crawler for loading or unloading the car.
A still further object of this invention is to provide new and improved adjustable pallets for removably mounting on the top of a gondola railroad car and adjustably spanning the bulging sides of the railroad car and supporting a crane-type crawler for loading and unloading the railroad car, wherein the adjustment feature includes spaced-apart, downwardly-extending leg assemblies, each having an adjustable inner sleeve-to compensate for the bulging of the gondola railroad car near the center thereof.